Posted 2012-May-28, 10:21
A self-referential comment by Steve McIntyre concerning the "Hockey Stick" and the IPCC methods and manners.
Posted May 27, 2012 at 7:03 AM | Permalink | Reply
In 2005 before ar4, I wrote the following response at Roger Pielke’s to the question about whether the Hockey Stick “mattered”. I didn’t get interested in it because it seemed like a vulnerable topic but because it was presented to the public, at least in Canada, not as an incidental argument, but as one of the major arguments, particularly for action right that instant.
Stefan Rahmsdorf and others (including Roger Pielke, the proprietor of this site) have taken the position that the Hockey Stick is irrelevant to the great issue of the impact of 2xCO2 on global climate. Even the originator of the Hockey Stick, Michael Mann, who received many awards and honors for its construction, ironically has taken the position that it doesn’t “matter”. (I do not believe that he has not returned any of the honors.) I’m inclined to agree that, for the most part, the Hockey Stick does not matter to the great issue of the impact of 2xCO2. However, I believe that it matters (or should matter) to IPCC, to governments that relied on IPCC and to climate scientists who contributed to and supported IPCC and to people who may wish to rely on IPCC in the future.
The Hockey Stick was not, as sometimes portrayed, an incidental graphic, buried in IPCC TAR. Nor was it an icon resurrected by sceptics purely to torment poor Michael Mann. It could almost characterized as the logo for IPCC TAR. Figure 1 below shows Sir John Houghton, at the press conference releasing IPCC TAR, standing in front of the Hockey Stick. The graphic was used repeatedly in IPCC TAR and was one of the most prominent graphics in the Summary for Policymakers. Some governments (and, the Canadian government in particular) relied upon it in their promotion of Kyoto policy even more than IPCC. In the lead-up to adopting Kyoto policy, Canadians were told by their Minister of the Environment that “1998 was the warmest year of the millennium and 1990s the warmest decade”. So even if the Hockey Stick did not “matter” to the scientific case, it mattered to the promotion of the scientific case. Scientists may want to “move on”, but institutions cannot, if they want to maintain any credibility. If the Hockey Stick was wrong, it would be as embarrassing as the failure to find WMD in Iraq. In both cases, the policy might well be justified on alternative grounds, but the existence of the alternative grounds does not mean that responsible agencies should not try to isolate the causes of intelligence failure and try to avoid similar failures in the future.
The issues surrounding the MBH Hockey Stick are complicated by IPCC TAR statements and decisions, which, in retrospect, seem misguided, although there is little to suggest that IPCC AR4 is taking to steps to avoid similar potential problems. The most questionable IPCC statement about the Hockey Stick is that the MBH98 reconstruction had “significant skill in independent cross-validation tests”. I added bold to highlight the plural—a second level to the misrepresentation contained in this claim. The statement appears to have been written by Michael Mann about his own work. It is now known that the MBH98 reconstruction in the controversial 15th century portion failed the majority of cross-validation tests, including the standard R2 test [McIntyre and McKitrick, 2005a]; the source code provided to the Barton Committee shows that the adverse cross-validation R2 statistics were calculated, but not reported. It is also now known that the MBH98 reconstruction does not live up to its warranty that it is robust to the presence/absence of all dendroclimatic indicators, as the reconstruction depends on the inclusion of bristlecones, a series known to be potentially contaminated as a temperature proxy. Again, this adverse information was known to the authors and not reported.
If I were in Houghton’s shoes, I would be mad as a boil about all this. Since Houghton has a sincere belief that the impact of 2xCO2 is the great issue of our times, then, if I were Houghton, I would be particularly angry at being placed in a position where I used this logo and wasn’t fully informed about adverse information pertaining to it. I also wouldn’t be leaving it up to some probably adversarial committee like the Barton Committee to sort this out. I’d be all over the problem so that my community, the community of climate scientists, was not further embarrassed and so that government institutions would be able to rely confidently on the opinions of IPCC.
If I were Houghton, one line of argument that I would not accept is that the other “independent” studies all say similar things. It was the Mann study that I stood in front of. If there are serious problems in it, which were known ahead of time and I didn’t know about them, I would carve everyone involved a new you-know-what. Now for public purposes, I’d feel a lot happier if I could at least retreat to the safe haven of other studies that showed something at least similar to the Mann study. But I’d be pretty worried about them on a couple of counts and I’d want them torn through from top to bottom. The first thing that would worry me is that the studies were not really “independent”. The coauthors all seem to swap places: you see Mann, Jones, Briffa, Bradley, Cook, Schweingruber – all well-known scientists, but all having coauthored together. I’d be worried about a monoculture and want a fresh set of eyes. The second thing that would worry me is that the same proxies are used over and over – the bristlecones, the Polar Urals etc. I’d be worried about systemic problems. I’d be worried that no one seemed to have gone through these other studies like M&M had gone through the MBH studies. Maybe there are more time-bombs. I wouldn’t just passively wait for them to go off.
If I were Houghton, I would be enraged at the public refusal by IPCC authors to show their data and methods. When I read in the Wall Street Journal that Mann had said that he would not be “intimidated” into showing his algorithm, I’d have taken immediate action; I’d have told Mann to stop acting like a prima donna, to archive every line of code and data used in MBH98 and stop fighting a pointless battle that simply embarrassed IPCC and the entire field of climate science. I’d have done more than that. I’d have notified everyone contributing to IPCC that we did not expect the same kind of nonsense any more, that anyone contributing to IPCC would have to ensure that their archives of data and methodology were complete or else we couldn’t use their articles. I’d have done so before I heard from some redneck Republicans.
I would also review how we were checking studies in IPCC AR4. If our very logo for IPCC TAR blew up on us, then something was wrong with our procedures for review. I wouldn’t go around patting ourselves on the back and telling everyone that this was the most “rigorous” review procedure in the history of science, since we’d goofed on such a prominent issue. I’d want to know why we goofed and how to avoid it in the future, or at least, how to minimize the chances of a recurrence. So when some redneck tried to use the Hockey Stick fiasco against IPCC, I’d at least have an answer.
A final thing that I’d ask myself: if this damn chart is “irrelevant” to the great issue of 2xCO2, why did we use it at all? And why did we rely on it so much in our sales presentations? Why didn’t we just talk about the issues that were important and stay away from little irrelevant stuff? Maybe I’d find out, when I investigated, that someone had decided that this was merely for sales promotion – the climate equivalent of a sexy girl sitting on a car. If that were the case, I wouldn’t necessarily be happy about it, but at least I’d understand it. Then I’d want to make sure that we were also selling steak as well as sizzle. I’d sure want to make sure that we’d really done a good job on the issue which Ramsdorff and others now say was the “real” issue: climate sensitivity to 2xCO2.
Here I’d be bothered by how little guidance we actually gave to policymakers interested in an intermediate-complexity analysis of whether 2xC02 will lead to a temperature increase of 0.6 deg C or 2.6 deg C or 5.6 deg C. When I re-examined the TAR, I’d notice that we’d virtually skipped over these matters. I’d think: it’s not enough just to list all the results of different models; let’s try to figure out why one model differs from another, what are the circumstances under which a model gives a low sensitivity and what are the circumstances that a model has high sensitivity – if that’s the “real issue”. When I saw that we’d barely touched this sort of analysis in IPCC TAR, I’d be pretty embarrassed. I would certainly vow that in AR4, we would not repeat the mistake of ignoring the “real issues” in favor of hood ornaments.
The other thing that I wouldn’t do is simply ignore the problem and hope that it goes away of its own accord. I wouldn’t rely on the assurances of Mann and similar protagonists that the various alleged defects do not “matter”. No corporation would do so in similar circumstances and IPCC shouldn’t either. I would long ago have got some independent statistician to see if there really was a problem that I should be worried about. I wouldn’t have stood still for this water torture. I’d tell Mann to co-operate with the investigator and request McIntyre to cooperate. I’d try to get the parties to sign off on an exact statement of points and issues that everyone agreed on and ones that were in dispute. Once I saw what was in dispute, I’d ask for what would be involved to determine once and for all who was right on specific issues. I would long ago have gotten tired of barrages from both sides, where I couldn’t be sure that they were not at cross-purposes.
So does the Hockey Stick matter? Yes, if you’re a climate scientist that believes that the IPCC is an important institution whose opinions should be valued. Mann now thinks that the Hockey Stick does not matter. As so often, life is full of ironies.
At the time, I sharply criticized the use of conflicted scientists to carry out controversial assessments – Keith Briffa was about the worst possible choice. This caveat proved out, as one of the worst revelations of the Climategate dossier was Briffa’s surreptitiously allowing Eugene Wahl, a party to the dispute, to insert assessment language in the report that varied from that sent out to external reviewers, to an assessment that more or less endorsed Wahl and Mann’s side of the dispute from the more agnostic assessment that had been sent out to reviewers.
The destruction of emails that Jones later instigated pertained to these review comments. And rather than coming clean, the University has fought disclosure of Wahl’s edits tooth and nail. All of this leaves a very unsavory impression of the people.
The people who should care about policy action of some sort, such as Allen, are the ones who should have been most concerned about getting to the bottom of what Mann, Briffa etc had done and whether there stuff constituted real “science” or was little better than paleophrenology. And should have been the ones that were most resolute in ensuring transparent and thorough inquiries.
The wider climate community took a great risk to their own credibility by idly standing by. The price has been that the credibility of the entire community has been tarnished at a time when their advice is important. That’s too bad.
But instead of blaming others, they should look in the mirror.
The Grand Design, reflected in the face of Chaos...it's a fluke!
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Daniel1960, on 2012-May-17, 12:24, said:
